However, it is well known that a corrosive power struggle within the ANC brought the confrontation to a head.

President Jacob Zuma's quest for re-election was set to be opposed by Malema and his powerful allies at an ANC elective conference late next year. Zuma will hope Thursday's verdict has delivered the knockout punch, robbing Malema of his constituency and leaving him a clear run to a second term.

But the duel between the Zuma and Malema factions points to a deeper faultline within Africa's oldest liberation movement as it approaches its centenary in January. It is essentially an unfinished dialogue with the vision of the first black president, Nelson Mandela.

Zuma came to power in 2009 as a compromise candidate, not because of what he stood for, but because he wasn't Thabo Mbeki, dispatched by the party in another "elephant" moment. Corruption allegations against Zuma were conveniently shelved in the interests of the coup. That he was described as "not having an ideological bone in his body" was seen as irrelevant, possibly advantageous.

As president, Zuma has steered a middle course, striving to create jobs in the teeth of a global financial crisis, promising to improve public service delivery, trying to position South Africa as an emerging global power open for trade. He has more or less maintained the status quo.

But Malema presents a troubling, disruptive alternative. Although he often cites Mandela's own irreverent youth league days as an inspiration, his pronouncements imply that the Mandela generation left the revolution unfinished.

They achieved political liberation, Malema argues, but not economic liberation. Mandela's miracle of forgiveness and reconciliation is all very well, and it saved white people from "being driven into the sea", but it also let them off the hook. Seventeen years into democracy, they still control most of the country's wealth, go to better schools and have better life chances. An average black man earns around R2,400 (£189) a month, while an average white man earns R19,000 (£1,493) in the world's most unequal society.

"The fact that the average life expectancy of white South Africans is more than 30 years higher than the life expectancy of their black counterparts is evidence enough that our people are facing extinction because of racialised poverty inherited from apartheid," Malema said recently.

"Our people are dying due to poverty and starvation because we have not changed the economic ownership pattern that is informed by apartheid."

From this he has forged a world view that is more Mugabe revolution than Mandela rainbowism. Whereas the founding fathers of democratic South Africa preached non-racialism, Malema has caused uproar with his singing of the protest song Shoot the Boer‚ a reference to Afrikaner farmers.

While many believe land reform and restitution has been too slow, Malema said bluntly that white people should be treated as criminals for stealing land from black people. The demagogue's demand that mines be seized from "white monopoly capital" and nationalised has spooked foreign investors.

On the international stage, Malema claims the inheritance of African nationalists. He has visited Mugabe like an apprentice paying respect to a mentor and dismissed Zimbabwe's Movement for Democratic Change as a tool of the neocolonial west. He condemned Zuma's government for supporting the Nato intervention in Libya and hailed Muammar Gaddafi as a martyr. Even his removal of a BBC journalist from a press conference contained a reference to a "white tendency".

It was Malema's claim that Botswana is in "full co-operation with imperialists … undermining the African agenda", and his pledge that the youth league would set up a command team to oppose the "puppet regime of Botswana", that sealed his fate with the ANC's disciplinary committee. Such remarks were reckless and baseless, they concluded.

His argument that "the African agenda is generally no longer a priority", and that "in the past, we know that President Mbeki used to represent that agenda very well", also proved his undoing.

Malema has distorted his leftwing credentials with outrageous behaviour. The self-appointed spokesman for the poor lives like a king and is under police investigation for corruption. A day after leading a creditable "economic freedom march" in Johannesburg and Pretoria, he jetted off to a R10m (£786,000) wedding in Mauritius at a luxury resort. Some say he has little genuine support and his headline-grabbing antics, along with the suspicion he is motivated by self-enrichment, have distorted a just cause.

But his removal does not mean the cause will go away. Nor will the battle for the soul of the ANC between what might be termed Mandela moderates and the young, angry, radical wing demanding swift remedy, whatever the pain. The conflict can often be observed in foreign policy, where South Africa oscillates awkwardly between western and African identities and loyalties; it gave confused signals on Ivory Coast and Libya this year.

The mass of black unemployed youth is often referred to as a ticking timebomb. One commentator predicted that in 2020 South Africa would have its Tunisia day. The ANC knows Malema is merely a symptom and it must connect with the millions he purports to speak for.